We need two measures to know if a hat fits your doggie.
1 : H > the circumference of the head just in front of the ears. (yellow line in the image below)
2: N > the circumference of the neck just under the head where it starts to get larger. (yellow line in the image below)
please use a tape-measure to have the correct size. The knitters are used to work with inches, but we can work from centimeters.
Include these measurements H & N in your order message.